14 research outputs found
Andromeda's Parachute: A Bright Quadruply Lensed Quasar at z=2.377
We present Keck Cosmic Web Imager spectroscopy of the four putative images of
the lensed quasar candidate J014709+463037 recently discovered by Berghea et
al. (2017). The data verify the source as a quadruply lensed, broad
absorption-line quasar having z_S = 2.377 +/- 0.007. We detect intervening
absorption in the FeII 2586, 2600, MgII 2796, 2803, and/or CIV 1548, 1550
transitions in eight foreground systems, three of which have redshifts
consistent with the photometric-redshift estimate reported for the lensing
galaxy (z_L ~ 0.57). By virtue of their positions on the sky, the source images
probe these absorbers over transverse physical scales of ~0.3-21 kpc,
permitting assessment of the variation in metal-line equivalent width W_r as a
function of sight-line separation. We measure differences in W_r,2796 of <40%
across all sight-line pairs subtending 7-21 kpc, suggestive of a high degree of
spatial coherence for MgII-absorbing material. W_r,2600 is observed to vary by
>50% over the same scales across the majority of sight-line pairs, while CIV
absorption exhibits a wide range in W_r,1548 differences of ~5-80% within
transverse distances less than ~3 kpc. J014709+463037 is one of only a handful
of z > 2 quadruply lensed systems for which all four source images are very
bright (r = 15.4-17.7 mag) and are easily separated in ground-based seeing
conditions. As such, it is an ideal candidate for higher-resolution
spectroscopy probing the spatial variation in the kinematic structure and
physical state of intervening absorbers.Comment: Submitted to ApJL. 9 pages, 3 figures. Uses aastex61 forma
MAGIQ at the W. M. Keck Observatory: initial deployment of a new acquisition, guiding, and image quality monitoring system
The W. M. Keck Observatory has completed the development and initial deployment of MAGIQ, the Multi-function Acquisition, Guiding and Image Quality monitoring system. MAGIQ is an integrated system for acquisition, guiding and image quality measurement for the Keck telescopes. This system replaces the acquisition and guiding hardware and software for existing instruments at the Observatory and is now the standard for visible wavelength band acquisition cameras for future instrumentation. In this paper we report on the final design and implementation of this new system, which includes three major components: a visible wavelength band acquisition camera, image quality measurement capability, and software for acquisition, guiding and image quality monitoring. The overall performance is described, as well as the details of our approach to integrating low order wavefront sensing capability in order to provide closed loop control of telescope focus
The Team Keck Treasury Redshift Survey of the GOODS-North Field
We report the results of an extensive imaging and spectroscopic survey in the
GOODS-North field completed using DEIMOS on the Keck II telescope. Observations
of 2018 targets in a magnitude-limited sample of 2911 objects to R=24.4 yield
secure redshifts for a sample of 1440 galaxies and AGN plus 96 stars. In
addition to redshifts and associated quality assessments, our catalog also
includes photometric and astrometric measurements for all targets detected in
our R-band imaging survey of the GOODS-North region. We investigate various
sources of incompleteness and find the redshift catalog to be 53% complete at
its limiting magnitude. The median redshift of z=0.65 is lower than in similar
deep surveys because we did not select against low-redshift targets. Comparison
with other redshift surveys in the same field, including a complementary
Hawaii-led DEIMOS survey, establishes that our velocity uncertainties are as
low as 40 km/s for red galaxies and that our redshift confidence assessments
are accurate. The distributions of rest-frame magnitudes and colors among the
sample agree well with model predictions out to and beyond z=1. We will release
all survey data, including extracted 1-D and sky-subtracted 2-D spectra, thus
providing a sizable and homogeneous database for the GOODS-North field which
will enable studies of large scale structure, spectral indices, internal galaxy
kinematics, and the predictive capabilities of photometric redshifts.Comment: 17 pages, 18 figures, submitted to AJ; v2 minor changes; see survey
database at http://www2.keck.hawaii.edu/realpublic/science/tksurvey
MAGIQ at the W. M. Keck Observatory: initial deployment of a new acquisition, guiding, and image quality monitoring system
The W. M. Keck Observatory has completed the development and initial deployment of MAGIQ, the Multi-function Acquisition, Guiding and Image Quality monitoring system. MAGIQ is an integrated system for acquisition, guiding and image quality measurement for the Keck telescopes. This system replaces the acquisition and guiding hardware and software for existing instruments at the Observatory and is now the standard for visible wavelength band acquisition cameras for future instrumentation. In this paper we report on the final design and implementation of this new system, which includes three major components: a visible wavelength band acquisition camera, image quality measurement capability, and software for acquisition, guiding and image quality monitoring. The overall performance is described, as well as the details of our approach to integrating low order wavefront sensing capability in order to provide closed loop control of telescope focus
Down-Regulated NOD2 by Immunosuppressants in Peripheral Blood Cells in Patients with SLE Reduces the Muramyl Dipeptide-Induced IL-10 Production
Pattern recognition receptors (PRRs) such as Toll-like receptors are aberrantly expressed of peripheral blood mononuclear cells (PBMCs) in systemic lupus erythematosus (SLE) patients, for playing immunopathological roles. basal productions of cytokines (IL-6, IL-8 and IL-10) were significantly increased in immunosuppressant naïve patients and patients with active disease despite immunosuppressants compared with HCs. Upon MDP stimulaiton, relative induction (%) of cytokines (IL-1β) from PBMC was significantly increased in immunosuppressant naïve patients with inactive disease, and patients with active disease despite immunosuppressant treatment compared with HCs. Immunosuppressant usage was associated with a decreased basal production and MDP induced relative induction (%) of IL-10 in patients with inactive disease compared with immunosuppressant naïve patients and HCs.Bacterial exposure may increase the NOD2 expression in monocytes in immunosuppressant naïve SLE patients which can subsequently lead to aberrant activation of PBMCs to produce proinflammatory cytokines, implicating the innate immune response for extracellular pathogens in the immunopathological mechanisms in SLE. Immunosuppressant therapy may downregulate NOD2 expression in CD8+ T lymphocytes, monocytes, and DCs in SLE patients which subsequently IL-10 reduction, contributing towards the regulation of immunopathological mechanisms of SLE, at the expense of increasing risk of bacterial infection
Internal Transcribed Spacer Region Sequence Heterogeneity in Rhizopus microsporus: Implications for Molecular Diagnosis in Clinical Microbiology Laboratories â–¿
Although internal transcribed spacer region (ITS) sequence heterogeneity has been reported in a few fungal species, it has very rarely been reported in pathogenic fungi and has never been described in Mucorales, causes of the highly fatal mucormycosis. In a recent outbreak investigation of intestinal mucormycosis due to Rhizopus microsporus infection in patients with hematological malignancies, PCR of the ITS of four of the 28 R. microsporus strains, P11, P12, D3-1, and D4-1, showed thick bands at about 700 bp. Direct sequencing of the purified bands showed frequent double peaks along all of the sequence traces and occasional triple peaks for P12, D3-1, and D4-1. The thick bands of the four R. microsporus strains were purified and cloned. Sequencing of 10 clones for each strain revealed two different ITS sequences for P11 and three different ITS sequences for P12, D3-1, and D4-1. Variations in ITS sequence among the different ribosomal DNA (rDNA) operons in the same strain were observed in only ITS1 and ITS2 and not the 5.8S rDNA region. One copy of P11, P12, and D4-1, respectively, and one copy of P11, P12, D3-1, and D4-1, respectively, showed identical sequences. This represents the first evidence of ITS sequence heterogeneity in Mucorales. ITS sequence heterogeneity is an obstacle to molecular identification and genotyping of fungi in clinical microbiology laboratories. When thick bands and double peaks are observed during PCR sequencing of a gene target, such a strain should be sent to reference laboratories proficient in molecular technologies for further identification and/or genotyping